Panel structures that are known in the art have used bendable panels and panels with a combination of connecting devices and frames to create structures.
Generally, panel structures used for shelter or habitation have evolved into spherical forms when they have entirely been constructed of panels. This form results because of its structural and geometric efficiency. Generally aligned in some manner related to geodesics, which reduce the numbers of different types of component parts, experimental thin panel structures have been constructed to 40' diameter using bent 1/4" plywood sheets bolted together face to face on overlapping portions of the panels. These structures have relied on bending to achieve the spherical curvature and therefore generally have been constructed of thin panels without adequate strength to support surface loading and have had long portions of their edges or surfaces in contact.
The basic frame geodesic structure, as is known in the art, has a basic frame structure normally covered with an appropriate skin or array of surface panels to provide a weather-tight enclosure. Surface panels generally can be thick enough to support surface loading as they do not bend, but rather, meet angularly along the lines of the geodesic frame structure to which they are attached for support. In some cases, where the frame elements are pre-attached to the surface panels, the structures could be called panel structures although the load bearing parts of the structure are comprised of the frame. However, no significant bending forces or axial loads are imposed on the panels, with the exception of their own weight and applied surface loading as described above.
Additionally, some kind of attachment device is required at the intersections of the structural panels or frames. Bolts, nuts, straps, clamps, and similar securing devices have been used in the past. Normally, such fasteners are made of metal and require special tools for securing the same. Further, where bolt holes and the like are provided, fairly close tolerances and angular preciseness must be maintained in the dimensioning of all of the component parts in order that proper registration will occur to enable proper fastening of the various panels to the frame. U.S. Pat. No. 4,308,698, issued to this inventor on Jan. 5, 1982, and incorporated herein by reference, discloses bendable panels that are also used to simplify the methods of connection. However, the preferred embodiment provides a frame structure where only the connecting device is the bendable portion of reference. Although another embodiment having a bendable structure is disclosed, it utilizes continuous edges for connection, and the flexibility required necessitates thin panels unable to support surface loading. Additionally, in its spherical form, all of the panels are triangular.
All of the foregoing characteristics of prior art structures make the assembly and disassembly of such structures a time-consuming operation. Moreover, because of the various different types of fastening means employed, not only are special tools required, but the overall expense of manufacture and of the materials employed is greater. Using fewer different types of component parts and a wider selection of materials would reduce the overall cost.